Vacuum tube and method of manufacturing the same



Jilly 28, 1925.

W. F. HENDRY VACUUM TUBE AND METHOD OF MANUFACTURING THE SAME Filed Sept. 4, 1919 Patented July 28, 1925.

UNITED STATES PATENT OFFICE.

WILLIAM FERRIS HENDRY, OF NEW YORK, N. Y., ASSTGN'OR TO ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y.,

VACUUM TUBE ANI D METHOD OF MANUFACTURING- THE SAME.

Application 111m September 4, 191a. 8er1a1No.321,6 72

To all whom it mag concern:

Be it known that 1, WILLIAM FERRIS HEN- DRY, a citizen of United States, residin at New York, in the county of New ork, State of New York, have invented certain new and useful Improvements in Vacuum Tubes and Methods of Manufacturing the Same, of which the following is a full, clear, concise, and exact description.

This invention relates to a method and apparatus for manufacturing vacuum tubes, and particularly one in which the use of the usual glass cane or stem for the support of the electrodes is avoided.

The object of the invention is the pro- Vision of a fusible insulating material in association with the electrode structure, whereby a more intimate and effective connection between the insulating material and the electrode structure can be achieved. One of the electrodes within the evacuated vessel, in conjunction with the insulating material, serves as a supporting unit for the other electrodes within thevessel, and thereby avoids the use of a glass cane or arbor, as a support for the electrode unit.

The invention comprises the provision of a block of glass within the vacuum tube, but s aced a art from the same, and associate with t e electrode structure so as to afford means for spacingsome of said electrodes and supporting others.

More particularly the use of this glass block in connection with the other electrodes is as follows:'

' One of the electrodes is connected at one end to a wall of the containing vessel. To the other end of this electrode, the block of glass is connected and from this blockof glass, by means of wires inserted therein, the other electrodes are supported, thereby roviding a rigid unitary structure which 1s self-supporting without theaid of glass I canes or arbors. This glass block may be been inserted and allow it to formed in any suitable manner, 'but a preferred manner is to pour molten glass into a mold into which the wires have previously cool. The glass more firmly and intimately grips the wires than other insulation materials into which wires have previously been inserted.

The invention'is illustrated .in the drawing, of which Fi 1 represents the preferred form of tube em odying the features of the invention, and Fig. 2 represents a perspective view of the glass block with the wires imbedded therein.

' As illustrated, the vacuum tube comprises an evacuated vessel 1 having a glass squash or press 2. An electrode '3, which is shown in the form of a double surface electrode has A coaronarrou or new YORK. i

a collar 4 at its lower end. The'abutting ends of the collar 4 are suitably welded together, whereby the electrode 3 is rigidly supported from the press2." This electrode 3 is shown as (provided with reinforcing corrugations an ribs to give it the proper amount of rigidity. This electrode 3 is formed from raw material into an integral blank and then bent around so that the two surfaces of the electrode are arranged in an opposed parallel relation, asshownfwith the upper ends disconnected. 'A metallic box '5 is formed in suitable die members, and is slipped over 'theen'ds of the electrode surface 3 to provide a metallic connection and a spacing unit for the surfaces of electrode 3. Within thisbox'o isplaced' a block '6 of glass which hasbeen 'molded'to the proper form, and has imbedded therein'wires 7 and 8, these wires serving to support respectively a grid 9 and a filament 10. It is within the scope of my invention that the wires 7 and 8 may be suitably held in place in the box 5,

and molten glass be poured into the box around the wires thus forming a very effective union between the wires, the box and the various electrodes, which thereby are more effectively spaced. The grid, plate, and

filament are electrically connected attheir lower ends to the usual lead-in wires. The specific details of the structureof the tube shown in the-drawing and the method of making the double surface electrodes are de scribe in an application, Serial No.'217,565, filed February 16, 1918, in the name of Hendr and entitled Vacuum tubes, and in U. Patent No. 1,426,734, dated 22, 1922, in the name of W. F. Hendry, entitled Methods of manufacturing audions.

Fig. 2 shows the form of glass block used, and this block may be molded in place after the electrode "unit has been assembled. or it may be molded separately. A method and apparatus for separately molding the glass blocks with the wires inserted therein is shown and described in U. S. Patent No. 1,396,759, dated Nov. 15, 1921, in the name August .the glass block and the glass of the vessel itself, i. e., the glass block is not connected to the vessel, by a material similar in properties to itself, as by means of other insulating material such as a glass stem or the like.

hat is claimed is:

1. An electron discharge device comprising an evacuated vessel, a plurality of electrodes of which one is an anode, said anode having opposed parallel surfaces, a block of glass-supported by one end of said anode to space the surfaces thereof and serving as a support for another electrode, said block of glass being spaced apart from and connected to said vessel only-bymetallic material.

2. An electron discharge device comprising an evacuated vessel, a plurality ofelectrodes of which one is an anode, said anode having opposed parallel surfaces which are connected at one end to the vessel, a block of fusible material connected to the other end of saidanode to space the surfaces thereof and serving as a support for another electrode, said block being spaced apart from, and connected to said vessel only by metallic material.

'3. An electron discharge device comprising an evacuated glass vessel, a plate, a grid, and a filament, said grid being between the plate and filament, a block ofv glass supported by the innermost end of the plate, said block serving as a support for the grid and filament, said block of glass being spaced apart from and connected to said vessel only by metallic material.

4. An electron discharge device comprising an evacuated glass vessel, a plate, a grid. and a filament, av block of glass supported by the plate at the innermost end thereof, said block servin as a support for the grid and filament, and metallic means for supporting said plate from said vessel. 5. Anelectron discharge device compris ing an evacuated vessel, a plate electrode having opposed surfaces, a grid and a filament, said plate electrode being connected to the vessel at its lower end, a block of glass supported by the upper-end of the plate electrode to space the surfacesthereof and serving as a support for the grid and the filament, said block of glass being spaced apart and connected to said vessel only by metallic. material.

6. An evacuated vessel containing a thermionic unit, comprising a plate elect-rode having opposed surfaces, a grid and a filament, said plate electrode being connected to the vessel at its lower end, a block of glass supported by the upper end of the plate electrode to space the surfaces thereof and serving as a support for the grid and filament, said block of glass being spaced apart from and connected to said vessel only by metallic material.

7. An evacuated vessel containing a ther- 8. A method of manufacturing vacuum tubes, which comprises connecting a plurality of electrode'surfaces .to the stem of a tube, joining the other ends of said surfaces Within the vessel by a fusible insulating material, embedding supports in said insulating material and mounting other electrodes on said supports.

9. The method of manufacturing vacuum tubes which comprises connecting a plurality of electrodes at one end to the tube, forming a mold sect-ion at. the other end of said electrodes and pouring a fused insulatingmaterial into said section to space and support the electrodes.

10. A method of manufacturing vacuum tubes which comprises forming a block of insulating material having wires embedded therein and projectingtherefrom, assembling a plurality of electrodes, associating said block with one of said electrodes and supporting the other electrodes by said wires.

11. The method of manufacturing a multiple plate electrode forvacuum tubes which comprises maintaining electrode plates in proper space relation and a ply- 4 i ing molten insulating material to said p ates, permitting said material to cool to space and support the plates.

12. A vacuum tube having anode, cathode and control electrodes, a block of fusible insulating material supported by one of said electrodes and supporting wires for the other two electrodes projecting into said block.

A vacuum tube having anode, cathode and control electrodes, a block of insulating material supported by one of said electrodes, said block being; arranged at that end of the supporting electrode remote from the base of the tube, and means carried by said block for supporting the other electrodes.

14. A vacuum tube comprising an inwardthereof remote from said neck, and means ly projecting neck, anode, cathode and confor supporting said other electrodes from trol electrodes, a block of fusible insulating said block. i in material, one of said electrodes having an In Witness whereof, I hereunto sub- 5 integral portion mounted on and supported scribe my name this 28th day of August by said neck, said block being supported A. D., 1919. by said last-mentioned electrode at the end WVILLIAM FERRIS HENDRY. 

